Preparation of 1,2-butylene oxide

ABSTRACT

A process for preparing 1,2-butylene oxide by catalytic hydrogenation of vinyloxirane over a heterogeneous catalyst comprises using a catalyst comprising an element of subgroup I, VII or VIII of the periodic table, or mixtures of a plurality of these elements, in the presence or absence of one or more promoter elements, these elements and promoters having been applied by means of a vacuum vapor deposition technique to a support of metal foil or metal wire fabric.

DESCRIPTION

This application is a 0371 of PCT/EP95/00656, dated Feb. 23, 1995.

The present invention relates to a process for preparing 1,2-butyleneoxide by catalytic hydrogenation of vinyloxirane over a heterogeneouscatalyst.

The catalytic hydrogenation of vinyloxirane is known.

According to U.S. Pat. No. 2,561,984, the hydrogenation of vinyloxiranein ethanol over a palladium/activated carbon catalyst at 25° C./2 bargives n-butyraldehyde as main product after a reaction time of 3 hours.In contrast, Raney nickel as catalyst results in formation of mainlyn-butanol at 25° C. and 2 bar after a reaction time of 1.5 hours.Nothing is recorded about the formation of butylene oxide.

A paper by Aizikovich et al. (J. Gen. Chem. USSR, 28 (1958) 3076)describes the catalytic hydrogenation of vinyloxirane in methanol orethanol over platinum, palladium and Raney nickel catalysts. A supportedpalladium catalyst (1.8% by weight of palladium on calcium carbonate)results in formation of mainly n-butanol at 15° C./1 bar. In thisdocument, the most important intermediate in the hydrogenation isregarded as crotyl alcohol, although the formation of n-butyraldehyde isalso observed. In this paper too, there is no reference to the formationof butylene oxide.

In U.S. Pat. No. 5,077,418 and U.S. Pat. No. 5,117,013 it is reportedthat the hydrogenation of vinyloxirane solutions overpalladium-containing catalysts gives n-butyraldehyde as main product.Thus, hydrogenation of vinyloxirane together with tetrahydrofuran assolvent over a palladium/activated carbon catalyst (5% by weight ofpalladium on activated carbon) at from 50° to 55° C. and a pressure of3.5 bar gives, after a reaction time of 3 hours, a hydrogenation productcontaining 55% of n-butyraldehyde, only 27% of butylene oxide and 9% ofn-butanol.

If the hydrogenation is carried out over supported catalysts containingpalladium on aluminum oxide (5% Pd/Al₂ O₃), only traces of butyleneoxide are formed after a reaction time of 6 hours at from 25° to 55° C.and a pressure of 3.5 bar or after a reaction time of 4 hours at 100° C.and a pressure of 20.7 bar. Quantitative conversion givesn-butyraldehyde as main product at a selectivity of 87% or 78%.

In addition, the hydrogenation of vinyloxirane over Raney nickel ashydrogenation catalyst at 50° C. and 3.5 bar is described, with 58% ofn-butanol being formed as main product. The yield of butylene oxide is,at 41%, low. In the hydrogenation of vinyloxirane over a supportedplatinum catalyst (1% by weight of Pt/Al₂ O₃) at 100° C. and a hydrogenpressure of 20.7 bar, only 40% of butylene oxide together with 23% ofn-butanol, 24% of various butenols, 5% of crotonaldehyde and 3% ofn-butyraldehyde are found for complete conversion after a reaction timeof 4.6 hours. Other platinum-containing catalysts give even lowerbutylene oxide yields.

Furthermore, U.S. Pat. No. 5,077,418 and U.S. Pat. No. 5,117,013 teachthat high butylene oxide yields are only obtained usingrhodium-containing catalysts. Various supported rhodium catalysts (5% byweight of rhodium on activated carbon; 5% by weight of rhodium onaluminum oxide), which have a high content of the expensive noble metalrhodium, or hydrated rhodium oxide (Rh₂ O₃.xH₂ O) give butylene oxidecontents of 60-93% in the hydrogenation of vinyloxirane solutions. Adisadvantage of this process is the low space-time yield based on theamount of rhodium used. Thus, the space-time yield in Example 2 of U.S.Pat. No. 5,117,013 is only 119 kg of 1,2-butylene oxide/kg Rh*h.

Neftekhimiya 33 (1993) 131 describes the hydrogenation of vinyloxiraneover catalysts containing nickel, palladium and copper. Using Raneynickel or nickel on kieselguhr as catalyst, the hydrogenation proceedsprimarily with opening of the epoxide ring which leads to thepredominant formation of 1-butenols and n-butanol. The yields ofbutylene oxide are low. For example, Raney nickel with methanol assolvent at 40° C./60 bar hydrogen pressure gives, after a reaction timeof 20 min at a conversion of 94%, a reaction product which, based onreacted vinyloxirane, contains 89% of butenols, 8% of n-butanol and only2% of butylene oxide. The hydrogenation of vinyloxirane in methanol at20° C./60 bar H₂ using freshly prepared Raney nickel also gives, after areaction time of 3 minutes at a conversion of 94%, only 9% of butyleneoxide in addition to 79% of n-butanol and 6% of butenol. A hydrogenationexperiment in methanol at 20° C./60 bar hydrogen pressure over a Raneynickel catalyst pretreated with isopropanol, nicotinic acid, pyridineand morpholine results, at 89% conversion, in the highest butylene oxideselectivity achievable using a nickel-containing catalyst, viz. 37%. Atthe same time, butenols and n-butanol are obtained in a selectivity 56%and 9% respectively.

With palladium-containing catalysts, higher butylene oxide selectivitiesare achieved in the hydrogenation of vinyloxirane compared with theexperiments using nickel-containing catalysts. For example, apalladium/activated carbon catalyst gives, without use of a solvent at15° C./60 bar hydrogen pressure after a reaction time of 13 minutes at61% conversion, 81% of butylene oxide based on converted vinyloxirane.On the other hand, under the same reaction conditions using methanol assolvent, a butylene oxide selectivity of only 53% is obtained at aconversion of 86%, with 13% of butanol and 18% of butenols being formed.A disadvantage of this process is that a high selectivity for theformation of 1,2-butylene oxide is achieved only at a relatively lowpartial conversion of the vinyloxirane. Since vinyloxirane and1,2-butylene oxide are very difficult to separate from one another bydistillation, this process is thus of no industrial importance.Palladium catalysts based on a polymer give, at a conversion of 68%,maximum butylene oxide selectivities of 60%, with butenol and n-butanolbeing formed in a selectivity of 18% and 4% respectively.

With copper-containing catalysts, a lower hydrogenation activity andresinification of the hydrogenation product is observed, making thisprocess industrially impractical. At reaction temperatures of 60°-100°C., 60 bar H₂ and 30% by weight of catalyst, a vinyloxirane conversionof 50% and a butylene oxide selectivity of 70% are achieved after areaction time of 3 hours.

It is an object of the present invention to provide an economicalprocess for preparing 1,2-butylene oxide from vinyloxirane in high yieldand selectivity. It is a further object to provide catalysts for thispurpose which achieve that object and, compared with prior artcatalysts, require significantly lower amounts of costly noble metals,especially rhodium or palladium, as catalyst component.

We have found that these objects are achieved by a process for preparing1,2-butylene oxide by catalytic hydrogenation of vinyl-oxirane over aheterogeneous catalyst, which comprises using a catalyst comprising anelement of subgroup I, VII or VIII of the Periodic Table, or mixtures ofthese elements, in the presence or absence of one or more promoterelements, these elements and promoters having been applied by means of avacuum vapor deposition technique to a support of metal foil or metalwire fabric.

The process of the present invention suprisingly makes it possible tohydrogenate the double bond of vinyloxirane (I) selectively according toequation (1) ##STR1## without the sensitive epoxide ring beinghydrogenolytically cleaved to any appreciable extent and withoutappreciable occurrence of other secondary reactions, for exampleisomerizations of vinyloxirane, for example to butyraldehyde orcrotonaldehyde, which are subsequently hydrogenated to butanol andcrotyl alcohol. Since the catalysts used according to the presentinvention have a very low content of the catalytically active, but verycostly, noble metals, such as rhodium and palladium, compared withother, prior art catalysts, the process of the present inventionprovides a very economical way of preparing 1,2-buty-lene oxide (II)selectively.

The catalysts used according to the present invention are prepared byusing a vacuum vapor deposition technique to apply the elements ofsubgroup I, VII or VIII of the periodic table, especially copper,silver, gold, rhenium, ruthenium, cobalt, rhodium, nickel, palladium orplatinum or mixtures thereof, to a metal support which may be in theform of metal foil or metal wire fabric.

As well as the elements of subgroup I, VII or VIII of the periodictable, it is additionally possible to apply promoter and/or stabilizerelements to the metal support. Such elements are for example theelements of main group IV and of subgroups II and IV of the periodictable, especially lead, tin, silicon, zinc, cadmium, titanium andzirconium. These elements, herein simply referred to as promoters, canbe applied to the metal support by vacuum vapor deposition techniquesindividually or mixed with other promoter elements together with one ormore of the elements of subgroup I, VII or VIII of the periodic table.

The catalytically active metals of subgroup I, VII or VIII of theperiodic table, or mixtures thereof, are generally applied to the metalsupport, with or without one or more of the promoter elements, in anamount of in general from 1 to 300 mg per m² of area of the metallicsupport material, preferably in an amount of from 20 to 200 mg per m² ofarea, especially in an amount from 40 to 100 mg per m² of area of themetallic support material. The promoter elements of main group IV or ofsubgroup II or IV of the periodic table, or mixtures thereof, aregenerally deposited on the metal support in an amount of in each casefrom 1 to 300 mg per m² of area of the metallic support material,preferably in an amount of from 20 to 200 mg per m² of area especiallyin an amount from 40 to 100 mg per m² of area of the metallic supportmaterial. The individual catalyst components--catalytically activeelements and promoter elements--can be deposited simultaneously orsuccessively.

The support materials used can be metal foils or wire fabrics woven fromvarious, weavable metal wires, such as iron, spring steel, copper,brass, phosphorus bronze, pure nickel, Monel, aluminum, silver, nickelbrass, nickel, chromium nickel, chromium steel, chromium nickel steeland also titanium. Particularly highly suitable support materials forthe process of the present invention are metal foils and especiallymetal wire fabrics in the materials bearing the material numbers 1.4767(alloyed high-grade steel, stainless, containing 19.0/22.0% by weightchromium, 4.0/5.5% by weight aluminum, ≦0.10% by weight carbon, ≦1.0% byweight silicium, ≦1.0% by weight manganese, ≦0.45% by weight phosphorand ≦0.030% by weight sulfur), 1.4401 (alloyed high-grade steel,stainless, containing 16.5/18.5% by weight chromium, 2.0/2.5% by weightmolybdenum, 10.5/13.5% by weight nickel, ≦0.07% by weight carbon, ≦1.0%by weight silicium, ≦2.0% by weight manganese, ≦0.45% by weight phosphorand ≦0.030% by weight sulfur) and 0 1.4301 (alloyed high-grade steel,stainless, containing 17.0/19.0% by weight chromium, 8.5/10.5% by weightnickel, ≦0.07% by weight carbon, ≦1.0% by weight silicium, ≦2.0 byweight manganese, ≦0.45% by weight phosphor and ≦0.030% by weightsulfur). The designation of these materials with the abovementionedmaterial numbers in accordance with the material numbers specified inStahleisenliste, published by Verein Deutscher Eisenhuttenleute; 8thedition, pages 87, 89 and 106, Verlag Stahleisen mbH, Dusseldorf 1990.The material bearing material number 1.4767 is also known as Kanthal.

Suitable support material for the catalysts which are usable in theprocess of the present invention include, as well as metal foils, metalwire wovens in different constructions, for example plain wovens, twillwovens, galloon wovens, five end satin wovens including fancy weaves.Other advantageous support materials include shaped articles formed frommetal foils, metal wire wovens or wire knit, for example spirals,Raschig rings or monoliths.

These metal supports are advantageously subjected to an oxidativetempering prior to their coating with the catalytically active metalsand any promoters. The oxidative tempering of these supports involvesheating them, preferably in air, to temperatures of from 600° to 1100°C., preferably to temperatures of from 750° to 1000° C.

The metal foil or wire woven, optionally following a preceding oxidativetempering, is coated by means of a vacuum vapor deposition techniquewith thin films of the catalytically active metals and optionally thepromoters. Thin films have a thickness ranging from a few angstrom tonot more than a few micrometers. The film thickness can be measured bymeans of a vibrating quartz crystal.

Suitable vacuum vapor deposition techniques include for example thermalvaporization, flash vaporization, cathode sputtering and also thecombination of thermal vaporization and cathode sputtering. Thermalvaporization can be effected by direct or indirect electric heating.Another possibility is electron beam vaporization. It involves using anelectron beam to heat the surface of the substance to be vaporized, in awater-cooled crucible, to such an extent that even high melting metalsand dielectrics can be vaporized.

These methods provide an optimum way of coating the catalyst supportspecifically with the catalytically active elements and any promoters.Alloys are preferably applied by flash vaporization.

The metal support can be vaporized batchwise or continuously in a vacuumvapor depositor, for example by using an electron beam, in a vacuum offrom 10⁻² to 10⁻¹⁰, preferably from 10⁻⁴ to 10⁻⁸, Torr to heat theactive component to be applied to such an extent that the metalvaporizes out of the water-cooled crucible and deposits on the support.The support material is advantageously arranged in such a way as tomaximize the proportion of the vapor stream which condenses on thesupport. The metal supports can be coated continuously by means of abuilt-in winding machine. Wire knits, for example Raschig rings formedfrom fine wires, can be introduced for example into a rotary drum basketfor loose stock and vapor-coated therein.

The vacuum vapor deposition techniques usable for preparing thecatalysts usable according to the present invention are themselves notpart of the subject-matter of the present invention. As regards thedetails of the procedure of coating the metal supports withcatalytically active metals and promoters reference is therefore made tohandbooks, for example Maissel, Glang, Handbook of Thin Film Technology,McGraw Hill, New York, 1970, and Vossen, Kern, Thin Film Processes,Academic Press, New York, 1978 or U.S. Pat. No. 4,686,202.

After the coating has been carried out, it can be advantageous tosubject the coated support material to a thermal conditioning treatmentby treating it, preferably in the presence of air or oxygen, attemperatures of generally from 20° to 800° C., preferably from 25° to700° C., for a period of generally from 0.5 to 2 h. Unless alreadycoated in that form, the metal foils or metal wire wovens can also beformed into shaped articles, such as Raschig rings, spirals andmonoliths, after the coating and conditioning, if desired.

The catalysts thus prepared can be used directly in the process of thepresent invention, but advantageously they are reduced before use in theprocess of the present invention, generally with hydrogen orhydrogen-containing gases at temperatures of typically from 50° to 300°C., preferably from 80° to 250° C. The reduction is generally carried onuntil the formation of water has ceased.

The process of the present invention involves hydrogenatingvinyloxirane, or solutions of vinyloxirane in a solvent which is inertunder the reaction conditions, in the presence of the catalysts to beused according to the present invention at temperatures of fromgenerally 0° to 200° C., preferably from 10° to 130° C., especially from20° to 100° C., and particularly preferably at from 40° to 100° C., at apressure of generally from 1 to 300 bar, preferably from 1 to 100 barand particularly preferably from 1 to 50 bar.

The process of the invention can be carried out without a solvent orpreferably in the presence of a solvent which is inert under thereaction conditions. Such solvents include for example ethers such astetrahydrofuran, dioxane, methyl tert-butyl ether, di-n-butyl ether,dimethoxyethane and diisopropyl ether, alcohols such as methanol,ethanol, propanol, isopropanol, n-butanol, iso-butanol and tert-butanol,C₂ -C₄ -glycols, hydrocarbons such as petroleum ether, benzene, tolueneand xylene, and N-alkyllactams such as N-methylpyrrolidone orN-octylpyrrolidone.

The process of the present invention can be carried out bothcontinuously and batchwise, in the gas phase or in the liquid phase. Acontinuous process can be carried out with advantage for example intubular reactors in which the catalyst is preferably arranged in theform of monoliths over which the reaction mixture is passed in theupflow or downflow mode. In the case of a batchwise process, not onlysimple stirred reactors or advantageously loop reactors can be used.When loop reactors are used, the catalyst is advantageously disposed inthe reactor in the form of monoliths or Raschig rings.

The reaction mixture can be worked up for 1,2-butylene oxide in aconventional manner, for example by distillation.

The vinyloxirane required as starting material can be prepared forexample by the process of U.S. Pat. No. 4,897,498 by partial oxidationof 1,3-butadiene over silver catalysts.

1,2-Butylene oxide is used, for example, as a motor fuel additive or asa stabilizer of chlorinated hydrocarbons.

EXAMPLES

In all examples the vacuum vapor deposition machine used was acommercially available electron beam vapor depositor from Balzers AG,Balzers (Duchy of Liechtenstein).

Example 1

A plain woven wire fabric in material No. 1.4767, having a mesh size of0.18 mm and a wire diameter of 0.112 mm, was heated in air at 950° C.for 5 h. The support woven thus pretreated was then coated withpalladium in an electron beam vapor depositor. The amount of palladiumdeposited was 92 mg of palladium per m² of area of the woven. Thecatalyst woven thus prepared was conditioned in air at 25° C. and thenused to produce 5×5 mm Raschig rings. In a 50 ml capacity autoclave, thesolution to be hydrogenated, comprising 2.5 g of vinyloxirane and 22.5 gof tetrahydrofuran, was admixed with 20 cm² of palladium-coated catalystwoven in the form of Raschig rings and hydrogenated with hydrogen at 50°C. and 40 bar over 6 h with stirring. The amount of palladium used wasthus 184 μg. Conversion was 100%, and the composition of the product was78.4 mol % of butylene oxide, 2.7 mol % of n-butyr-aldehyde and 3.3 mol% of n-butanol.

Example 2

The same wire woven as in Example 1 was heated to 1000° C. in air for 5h. After cooling, this support material was coated in the same vacuumvapor depositor as in Example 1 successively with 92 mg of palladium perm² of area of the support and 21.3 mg of lead per m² of support area. Tocondition the catalyst, the coated woven was tempered in air at 600° C.for 0.5 h. The woven was then shaped into 5×5 mm Raschig rings, whichwere activated in a quartz tube at 200° C. with hydrogen at atmosphericpressure and cooled down under a nitrogen atmosphere. In this form, 15cm² of the catalyst were used for the hydrogenation of 2.5 g ofvinyloxirane in 22.5 g of tetrahydrofuran. The hydrogenation was carriedout as described in Example 1. Conversion was 100%, and composition ofthe product was 83.9 mol % of 1,2-butylene oxide, 1.9 mol % ofn-butyraldehyde and 2.4 mol % of n-butanol.

Example 3

By the procedure of Example 1 the same wire woven was heated in air at1000° C. for 5 h and then vacuum coated in succession with 92 mg ofpalladium per m² of support area and 20.2 mg of gold per m² of supportarea and conditioned. After 5×5 mm Raschig rings had been formed, 18.75cm² of this catalyst were introduced into an autoclave and thehydrogenation of 2.5 g of vinyloxirane in 22.5 g of tetrahydrofuran wascarried out at 50° C. and 40 bar hydrogen pressure for 8 h. Conversionwas 100% and the composition of the product was 89.1 mol % of1,2-butylene oxide, 1.7 mol % of n-butyraldehyde and 1.0 mol % ofn-butanol.

Example 4

The same wire woven as in Examples 1 to 3 was heated at 950° C. for 5 hand, after cooling down, vacuum coated with 46 mg of palladium per m² ofarea and 6.1 mg of silicon per m² of area and conditioned. After thecatalyst woven had been shaped into 5×5 mm Raschig rings, 20 cm² of thiscatalyst were used for the hydrogenation run, which was carried outunder the same reaction conditions as described in Example 3. Conversionwas 97.7%, and the composition of the product was 85.3 mol % of1,2-butylene oxide, 1.2 mol % of n-butyraldehyde and 1.3 mol % ofn-butanol.

Example 5

The wire woven of Examples 1 to 4 was heated at 900° C. for 5 h and thencoated in the vacuum vapor depositor in succession with 46 mg ofpalladium per m² of area and 19.7 mg of zirconiun per m² of area andconditioned as in Example 1. The catalyst fabric was shaped into 5×5 mmRaschig rings and in this form 20.0 cm² of catalyst were introduced intothe hydrogenation autoclave. Then 2.5 g of vinyloxirane in 22.5 g oftetrahydrofuran were hydrogenated at 50° C. and 40 bar hydrogen pressurefor 4 h. Conversion was quantitative, and the composition of the productwas 84.6 mol % of 1,2-butylene oxide, 1.6 mol % of n-butyraldehyde and1.3 mol % of n-butanol.

Example 6

The same wire woven as in Examples 1 to 5 was following the samepretreatment as in Example 5 vacuum coated in succession with 46 mg ofpalladium per m² of area and 10.4 mg of titanium per m² of area andconditioned as in Example 1. The resulting catalyst fabric was shapedinto 5×5 mm Raschig rings and 21.25 cm² thereof were used for theautoclave run. It was carried out under the same reaction conditions asdescribed in Example 5. Conversion was complete, and the composition ofthe product was 82.4 mol % of butylene oxide, 1.6 mol % ofn-butyraldehyde and 2.1 mol % of n-butanol.

Example 7

The same wire woven as in Examples 1 to 6 was heated at 1000° C. in airfor 5 h. Nickel was then applied in the vacuum vapor depositor in anamount of 66 mg of nickel per m² of area, followed by conditioning as inExample 1. This catalyst fabric was used to make into 5×5 mm Raschigrings, which were activated with hydrogen at 230° C. as described inExample 2. 22.5 cm² of the activated catalyst were used for thehydrogenation run which was carried out under the same reactionconditions as described in Example 3. Conversion was 94.8%, and thecomposition of the product was 80.8 mol % of 1,2-butylene oxide, 1.7 mol% of n-butyraldehyde and 4.1 mol % of n-butanol.

Example 8

The same support woven as in Examples 1 to 7 was heated at 950 ° C. inair for 5 h. After cooling, it was vacuum coated in succession with 66mg of nickel per m² of area and 92 mg of palladium per m² of area andconditioned as in Example 1. After the catalyst woven had been shapedinto 5×5 mm Raschig rings, the catalyst was activated with hydrogen asdescribed in Example 7. 21.25 cm² of the activated catalyst were usedfor the hydrogenation. Under the same reaction conditions as describedin Example 1, conversion was complete and the composition of the productwas 84.0 mol % of butylene oxide, 2.3 mol % of n-butyraldehyde and 3.5mol % of n-butanol.

Example 9

The same woven as in Examples 1 to 8 was heated at 950° C. in air for 5h and, after cooling, coated in the vacuum vapor depositor in successionwith 66 mg of nickel per m² of area and 16.1 mg of rhenium per m² ofarea. To condition the coated woven, it was heated up to 600° C. in airfor 2 h and tempered at that temperature for 0.5 h. Then 5×5 mm Raschigrings were fabricated from the catalyst woven and 21.25 cm² of thecatalyst woven were used for the hydrogenation run. Under the samereaction conditions as described in Example 3 conversion wasquantitative and the composition of the product was 82.6 mol % of1,2-butylene oxide, 1.9 mol % of n-butyraldehyde and 4.3 mol % ofn-butanol.

Example 10

The woven of Examples 1 to 9 was heated at 1000° C. for 5 h and, aftercooling, vacuum coated in succession with 66 mg of nickel per m² of areaand 16.1 mg of palladium per m² of area and 16.1 mg of rhenium per m² ofarea. The woven was then heated to 600° C. in air over 2 h and temperedat that temperature for 0.5 h. Following the customary preparation of5×5 mm Raschig rings, the catalyst was activated under atmosphericpressure with hydrogen at 200° C. in a quartz tube. 21.25 cm² of theactivated catalyst woven were used for the hydrogenation run, which wascarried out under the same reaction conditions as described in Example3. Conversion was 97.2% and the composition of the product was 82.2 mol% of 1,2-butylene oxide, 1.7 mol % of n-butyraldehyde and 4.6 mol % ofn-butanol.

Example 11

The same woven as in-the preceding examples was heated at 1000° C. inair for 5 h. The support material thus pretreated was vacuum coated with88 mg of rhodium per m² of area. The coated fabric was then conditionedas in Example 1. The resulting catalyst woven was used to fabricate 5×5mm Raschig rings, and a catalyst woven quantity of 21.25 cm² was usedfor the hydrogenation of vinyloxirane carried out under the samereaction conditions as described in Example 3. Conversion was completeand the composition of the product was 86.0 mol % of 1,2-butylene oxide,4.0 mol % of n-butyraldehyde and 4.5 mol % of n-butanol. The space-timeyield based on the amount of rhodium used was 1,437 kg of 1,2-butyleneoxide/kg of Rh.h.

Example 12

Woven fabric heated at 1000° C. in air for 5 h as per the precedingexamples was coated in succession in the electron beam vapor depositorwith 24 mg of rhodium per m² of area and 46 mg of palladium per m² ofarea. For conditioning, the resulting material was heated over 1 h to500° C. in air and tempered at that temperature for 1 h. Afterpreparation of 5×5 mm Raschig rings from the resulting catalyst fabric,21.25 cm² were used for the hydrogenation run. The hydrogenation of 2.5g of vinyloxirane and 22.5 g of tetrahydrofuran at 50° C. and 40 barhydrogen pressure for 2 h proceeded with quantitative conversion and thecomposition of the product was 90.1 mol % of 1,2-butylene oxide, 1.8 mol% of n-butyraldehyde and 2.5 mol % of n-butanol.

Examples 13 to 17

20 cm² of the palladium-coated catalyst woven of Example 1 were used forhydrogenation runs for hydrogenating 2.5 g of vinyloxirane in 22.5 g ofdifferent solvents at 50° C. and 40 bar hydrogen pressure. Thecompositions of the reactor effluents are shown in the table.

                  TABLE    ______________________________________              Reaction                     Composition of reactor effluent    Ex. Solvent     time     VO   BO    n-BA  n-BuOH    ______________________________________    13  MTBE        1 h      --   83.4  2.3   1.7    14  Di-n-butyl ether                    2 h      --   78.9  0.9   1.0    15  Methanol    2 h      --   78.6  2.6   7.2    16  Ethanol     2 h      --   75.1  1.0   2.5    17  Toluene     2 h      --   77.0  1.8   2.5    ______________________________________     VO = Vinyloxirane     BO 1,2Butylene oxide     nBA = nButyraldehyde     nBuOH = nButanol     MTBE = Methyl tertbutyl ether

Example 18

Plain woven wire fabric in material No. 1.4301, having a mesh size of0.125 mm and a wire diameter of 0.100 mm, was heated at 800° C. in airfor 3 h. The support material thus prepared was then coated withpalladium in an electron beam vapor depositor. The amount of palladiumapplied was 92 mg of palladium per m² of area of support fabric. Thecatalyst thus prepared was used to make 5×5 mm Raschig rings. 2.5 g ofvinyloxirane and 22.5 g of tetrahydrofuran were introduced into a 50 mlcapacity autoclave, complemented with 21.25 cm² of the shaped catalystfabric, and hydrogenated at 50° C. and 40 bar hydrogen pressure for 7 hwith stirring. Conversion was 97.7% and the composition of the productwas 81.0 mol % of butylene oxide, 1.6 mol % of n-butyraldehyde and 4.6mol % of n-butanol, based on converted vinyloxirane.

Example 19

Plain woven wire fabric in the material of material No. 1.4401, meshsize 0.160 mm, wire diameter 0.100 mm, was heated at 850° C. in air for3 h, then vacuum coated with 92 mg of palladium per m² of area andconditioned as in Example 1. 21.25 cm² of this catalyst fabric in theform of Raschig rings were used to hydrogenate vinyloxirane andtetrahydrofuran similarly to Example 18. Conversion was 99.5%, and thecomposition of the reactor effluent was 79.3 mol % of 1,2-butyleneoxide, 1.9 mol % of n-butyraldehyde and 3.4 mol % of n-butanol.

Example 20

Wire woven in material of material No. 1.4767 was pretreated asdescribed in Example 1, vacuum coated with 161.2 mg of rhenium per m² ofarea of fabric and conditioned as in Example 1. 42.5 cm² of the catalystfabric thus prepared in the form of 5×5 mm Raschig rings were used tocarry out the vinyloxirane hydrogenation of Example 18 at 95° C. and 40bar hydrogen pressure. Following a reaction time of 8 h conversion was29.3% and the composition of the reaction mixture was 76.0 mol % of1,2-butylene oxide, 4.4 mol % of n-butyraldehyde and 4.7 mol % ofn-butanol, based on converted vinyloxirane.

Example 21

The wire woven in of Example 1 was heated at 950° C. in air for 5 h,then vacuum coated with 91.2 mg of ruthenium per m² of area of fabricand conditioned as in Example 1. 42.5 cm² of this catalyst fabric in theform of 5×5 mm Raschig rings were used in the hydrogenation. Thehydrogenation was carried out at 95° C. and a hydrogen pressure of 40bar. Conversion was 31.3% after 4 h and the composition of the productwas 83.4 mol % of 1,2-butylene oxide, 3.1 mol % of n-butyraldehyde and2.5 mol % of n-butanol, based on converted vinyloxirane.

Example 22

The catalyst fabric pretreated as in Example 1 was coated with 166.4 mgof cobalt per m² of fabric by vapor deposition and conditioned as inExample 1. 21.25 cm² of this catalyst fabric were used in the form ofRaschig rings (5×5 mm) for the hydrogenation of vinyloxirane. Thehydrogenation was carried out at 50° C. and 40 bar hydrogen pressure.Conversion was 40% after 24 h and the composition of the reactoreffluent was 83.2 mol % of 1,2-butylene oxide, 1.8 mol % ofn-butyraldehyde and 2.6 mol % of n-butanol, based on convertedvinyloxirane.

Example 23

The metal woven pretreated as in Example 1 was coated with 67 mg ofcopper per m² of area of fabric by vacuum vapor deposition andconditioned as in Example 1. 42.5 cm² of this catalyst woven were usedin the form of Raschig rings (5×5 mm) for the hydrogenation ofvinyloxirane at 95° C. and 40 bar hydrogen pressure. Conversion after 8h reaction time was 18%, and 89.6 mol % of 1,2-butylene oxide wasformed, based on converted vinyloxirane.

Example 24

The metal woven pretreated as in Example 1 was coated with 160 mg ofplatinum per m² of area of fabric by vapor deposition and conditioned asin Example 1. 21.25 cm² of this catalyst in the form of Raschig rings(5×5 mm) were used for the hydrogenation of vinyloxirane at 50° C. and40 bar hydrogen pressure. Conversion was 85.4% after 24 h and thereaction mixture contained 64.4 mol % of 1,2-butylene oxide, 3.6 mol %of n-butyraldehyde and 16.4 mol % of n-butanol, based on convertedvinyloxirane.

Example 25

The catalyst woven of Example 5 was made into Raschig rings and used inan amount of 40.0 cm² for the hydrogenation run. The hydrogenation of10.0 g of vinyloxirane at 50° C. and 40 bar hydrogen pressure in theabsence of a solvent proceeded with quantitative conversion after areaction time of 7 h, when the reaction mixture contained 83.9 mol % of1,2-butylene oxide, 1.0 mol% of n-butyraldehyde and 0.8 mol % ofn-butanol. The space-time yield, based on the amount of palladium used,was 6,522 kg of 1,2-butylene oxide/kg of Pd.h.

We claim:
 1. A process for preparing 1,2-butylene oxide by catalytichydrogenation of vinyloxirane over a heterogeneous catalyst, wherein thecatalyst comprisesan element of subgroup I, VII or VIII of the periodictable, or mixtures of a plurality of these elements, optionally one ormore promoter elements, and wherein the elements and promoters have beenapplied by means of a vacuum vapor deposition technique to a support ofmetal foil or metal wire woven with the proviso that the element ofsubgroup I, VII or VIII is not rhodium.
 2. The process defined in claim1, wherein the catalyst comprises one or more elements of main group IVor of subgroup II or IV of the periodic table as promoters.
 3. Theprocess defined in claim 1, wherein the metal foil or metal wire wovensupport is formed from materials bearing the material numbers 1.4767,1.4401 or 1.4301.
 4. The process defined in claim 1, wherein the supportis heated in air at from 600° to 1100° C. before the catalyticallyactive elements are applied.
 5. The process defined in claim 1 whereinthe catalyst comprises one or more elements of subgroup I, VII or VIIIof the periodic table applied to the metal support in an amount of ineach case from 1 to 300 mg/m² of area of the support.
 6. The processdefined in claim 1, wherein the catalyst, as well as the elements ofsubgroup I, VII or VIII of the periodic table, further comprisespromoter elements, these promoter elements having been applied to themetal support in an amount of in each case from 1 to 300 mg/m² of areaof the support.
 7. The process defined in claim 1, wherein the catalysthas been conditioned in air at from 20° to 800° C. after thecatalytically active elements were applied by means of a vacuum vapordeposition technique.
 8. The process defined in claim 1, wherein thecatalyst was reduced with hydrogen at from 20° to 300° C. before use.